In having to adopt a policy of seat swapping a company is showing that it has not dealt well with the problem of recruitment and retention of crew but that is the way of the world at the moment. The actual mechanics of operating from the RHS when you are well used to the LHS can become straightforward with proper sim training and a meaningful number of line training flights. Most people find the hardest task adjusting the seat properly when the levers have all moved! My main concern would be the CRM aspect of two captains flying together. In an ideal world it should present no problems as one (the more senior) is designated as the commander and away you go with lots of experience on hand to deal with anything that comes your way. In the vast majority of cases this will be what happens but there are always going to be times where having two "bosses" working together scuppers this. It probably won't be on a big issue as the SOP's should take care of that but a situation which requires a decision from someone to query the actions of their equal. It's one thing to ask of your F.O "Why did you do that?" or even for the F.O. to seek clarification of his Captains intent, it may be harder to challenge another captain as perhaps you would not wish to cause a loss of face. Operating from the RHS has never been an issue on line training flights as you are there in a training capacity and it is expected you will have more than the usual input into the actions of the person in the LHS.